| 摘要 |
<p>PURPOSE:To enable integral monitoring of various kinds of devices by installing in a place for monitoring an optical fiber connected to a pulse beam transmitter- receiver, and installing optical communications transmitter-receivers in a plurality of appropriately separate points on the optical fiber. CONSTITUTION:Should a pit 6 be inundated or a fire occur at a point 15 or a low-temperature fluid make contact with a point 16, scattering of transmitted light occurs at those portions of an optical fiber 5. In response to a signal from a transmitter-receiver 2, a processor 3 determines the position of the scattering as the distance along the optical fiber 5, from the delay time of backscattered light reflected. A position in premises which corresponds to the point where the backscattered light has occurred is specified in accordance with the distance and data on the installation of the optical fiber. The point is displayed on a display device 4, together with the map of the corresponding place in premises, etc.</p> |
